Hello AV,
From what has been written on the web, hair loss seems to be caused either by toxins disrupting the follicular growth or an electrolyte deficiency. This usually occurs after 20 days or so of water-only fasting.

Joel Fuhrman, M.D. has stated that Hair loss AFTER fasting is not uncommon, it even has a medical name called Telogen Effluvium. Telogen Effluvium results from the conversion of a large number on anagen (active) hairs to telogen (resting) hairs, with subsequent shedding.
It is usually observed 1 to 4 months after a precipitating event but may occur up to 8 months later. Typically less than 50% of hair is lost and be noticed only by the person suffering with it. Many drugs can cause this as well, but it also can be precipitated by rapid weight loss, fasting, surgery, childbirth, illness, infection and psychological stress. No treatment is necessary for this self-limiting disorder, although the duration varies form 6 to 12 months. Hair regrowth is always complete.

This is a link that lulu found and posted on some 20 months ago re' hair loss from Dr. Isabelle A. Moser................
http://www.soilandhealth.org/02/0201hyglibcat/020102moser/020102Moser03ch3.html


and this thread as well.......................
//www.curezone.org/forums/am.asp?i=1129463


The good thing is that hair loss (if it occurs) seems to be only of a temporary nature while fasting or thereafter, and where it usually does regrow better, thicker and healthier than before the fast.

I suppose you could say I am one example of this: I am 56 years of age and have fasted many times, with two prolonged fasts behind me, but I have a full head of hair that is shiny and thick with only a few gray ones that you could count on the fingers of one hand.
My brother on the other hand is almost 58 and is mostly bald...........he has never fasted; and my late father whose hair thinned-out markedly in his mid to late forties.

Hope this is helpful.

Chrisb1.